This invention relates to photographic film processors and more particularly to a method and apparatus for automatically determining the operational status of the processor. In developing photographic films, it is important to closely monitor a number of critical parameters, such as for example, the temperature and strength of the chemical developers employed, to insure that the proper film densities are achieved. It is sometimes possible to determine that one or more of these parameters is not correct by inspection of a normally developed film, but without more information, identification of the specific cause of improper processing is difficult.
Manual comparison of a developed film (produced from calibrated exposure of sections of the film) to predetermined density standards and analysis of the results of this comparison (sometimes requiring trial and error adjustments of the processor) is presently relied upon to determine the operational status of X-ray film processors in some hospitals. The general object of the present invention is to provide a method and apparatus for performing this function automatically.
This invention allows an operator to isolate the specific cause of improper development of a test film strip, by automatically measuring the densities of the film at three specific test areas, and then using the results of these measurements to determine the operational status of the processor. The operator can then make any required adjustments to the processor and proceed to develop other films without resorting to the usual trial and error approach to identify which parameters should be changed. This saves time and material and since the necessary adjustments are automatically indicated, this invention reduces the skill levels required of the personnel operating the film processor.